Funds are requested to support the attendance of ten young United States Scientists to the International Conference on the Crystal Growth of Biological Macromolecules to be held in July, 1987 at Bichenberg, France. The Principal Investigator is a co- organizer of this conference which follows by two years the First International Conference on Protein Crystal Growth held at Stanford University (August, 1985) which he also co-organized. The purpose of this conference is both to bring together scholars and scientists working on the general problem of macromolecular crystallization to discuss technical grounds for progress in research, and to disseminate knowledge currently available but rather difficult to obtain because of the diversity of interests involved. The topic is of substantial interest and significance to the biochemical and molecular biology research community because it treats a crucial phase in the determination of three dimensional protein structure by X-ray diffraction techniques. These determinations are impacting with increased force on the directions taken by protein engineering, rational drug design and a host of other fields employing recombinant DNA technology. Protein structure determinations are in themselves of profound importance as well, for they provide the basis of an understanding of the architectural principals and atomic levels mechanisms that guide protein function and regulation. Sessions at the Conference will include broad topics of practical concern such as new techniques, reagents, and approaches to protein crystallization, the theories of crystal nucleation and growth, an accounting of experiences, and exchange of ideas. Also included will be sessions more narrowly focused on topics such as membrane protein crystallization, crystallization to in microgravity, the crystallization of macromolecular complexes, and the interface of ideas relating protein crystallization the crystallization of conventional small molecules. Attendance by young American investigators interested in this field is essential to insuring that crystallography and molecular biology in the United States share in the benefits and rewards of this Conference.